Solar power is a kind of clean, pollution-free renewable energy, which has been the development trend of energy for next generation. One key technique commonly used for solar energy collection is maximum power point tracking (MPPT) which is configured to maximize power extraction under all conditions. The efficiency of power transfer from the solar panel depends on both the amount of sunlight falling on the solar panel and the electrical characteristics of the load. The load characteristic that provides the maximum power transfer efficiency is changed with sunlight exposure such that people can acquire the maximum power transfer efficiency through MPPT technique. Moreover, the solar panel cannot store electricity so that the solar panel usually connects to a lithium battery for electricity storage. Since lithium battery is easily broken when overcharging or over-discharging, it usually uses with battery management systems (BMS). During charge or discharge process, BMS is configured to monitor lithium batteries conditions including terminal voltage, temperature, charge and discharge current, and total voltage, and in order to prevent lithium batteries from being damaged by overcharging or over-discharging, BMS has the function of cutting off circuit of the system.
However, the conventional solar power apparatus is disadvantageous because: since BMS is configured to cut off circuit of the system when the lithium batteries are at low electrical potential due to over-discharging, and meanwhile the MPPT system is adapted to stop charging the lithium batteries. In this moment, the lithium batteries can only be charged by external battery which is manually connected by personnel, and the solar panel can only back to normal status until the lithium batteries are charged to normal electrical potential. Therefore, there remains a need for a new and improved design for a movable solar power apparatus to overcome the problems presented above.